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Remplir LV Monogram Canvas Shoulder Sac M51172 Café

Remplir LV Monogram Canvas Shoulder Sac M51172 Café

The high strain-rate (103−104 s−1) fracture properties and impact ignition sensitiveness of several typical in-service and research composition rocket propellants (HTPB/AP, HTPB/PETN, HTPB/RDX, Chaussure Louis Vuitton Pour Homme PEG,PCP/RDX,HMX, and a NC/NG (42:46) CDB) were assessed using a modified Hopkinson Bar. A microflash photography technique was used to photograph the deformation/fracture and ignition events during projectile impact. The predominant impact ignition mechanisms under various conditions of strain-rates, specimen geometry, and material properties were identified, and the stress-strain states related to deformation/fracture and ignition processes. In the HTPB/AP propellant, specimen geometry affects the relative extent of ductile and shear failure, but the Chaussure Louis Vuitton Monogram overall impact ignition mechanism is not altered. Photographic evidence of plastic deformation/flow and the role of shear in the impact ignition events were obtained for this propellant. The RDX and PETN propellants were in a rubbery-viscous state before ignition was evident. Viscous heating from viscoplastic work, after plastic deformation/flow produced localized melting in the regions of maximum shear stress, is responsible for the initiation of ignition. For the RDX propellant, there is some photographic evidence of ignition occurring in the gaseous phase. The PEG,PCP/RDX,HMX propellant exhibits the large-strain viscoelastic deformation behavior characteristic of elastomers and is one of the least sensitive to impact. Two very distinct phases, a solid layer and a “melt” layer, are observed. Ignition is confined in the “melt” layer, near the junction of the solid and molten layers, and is indicative of a viscous heating mechanism. For the CDB propellant, comparatively less plastic flow was observed and ignition occurred during/after brittle fracture around the grains Chaussures Louis Vuitton Homme Pas Cher of the propellant, suggesting that adiabatic heating at the tips of fast propagating cracks is a possible ignition mechanism.

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